1. Field of the Invention
The present invention relates to a wafer manufacturing system and a wafer manufacturing method, which can cope with a process module for processing an object to be processed (which will be hereinafter referred to xe2x80x9cwaferxe2x80x9d) such as a semiconductor substrate, a liquid crystal substrate or a component substrate.
2. Related Art
Conventionally, as disclosed in, for example, xe2x80x9cOperation Of LSI Production System Which Can Reduce Investment For Development and Cope With Variety Of Needsxe2x80x9d, Nikkei Micro-Device, August, 1992 Pages 66-74, the conveyance of an object to be processed among a plurality of processing units, have carried out such a manner that a plurality of wafers, that is, the so-called lot, as a unit, are conveyed in a batch. As far as the wafers are processed in a batch, a processing time corresponding to a number of wafers in a lot, is required in order to process the lot, and accordingly, the waiting time to the next process becomes longer.
On the other hand, as disclosed in JP-A-4-130618 and JP-A-7-122622, there have been proposed a manufacturing system and a manufacturing method which utilizes one-piece conveying devices for conveying wafers one by one among a plurality of processing units in series so as to shorten the complete process consisting of steps in series in order to aim at enhancing the yield.
In the conventional system, with the use of a plurality of processing units in series for processing, since no consideration has been made for avoiding crossing wafers to be conveyed one another, and the control and management of processing and conveying wafers one by one has been complicated, and accordingly, it has been very difficult in an actual mass-production firm in which wafers are successively processed. Further, since the total system consisting of a plurality of modules including various film forming units, a resist coating unit, various etching units and various inspection units is connected to a single ring-like piece conveying device such as, for example, a conveyer, through the intermediary of interface sections, the system becomes large-sized while a heavy load is exerted to the piece conveying device during mass production, resulting in considerable lowering of through-put. Further, for each of the processing units, a pair of transferring mechanisms for loading and unloading the wafers, a wafer identification device and a buffer are arranged in an interface unit between each of the various processing devices and the ring-like piece conveying device, and accordingly, the system becomes further complicate and large-sized.
Further, in another example, there has been proposed a loop-like piece conveying device utilizing a belt which turns around in two to four minutes while repeats a movement and a stop in a period of about 3 seconds. It is described that the delivery of a wafer between a processing unit and the loop-like conveying device is completed in one second within the above-mentioned period of about three minutes. However, it is difficult to surely deliver a wafer at such a high speed as mentioned above. Further, although for each of the processing unit, a wafer transferring robot should be provided in an inlet part thereof in order to deliver the wafer between the processing units and the conveying device, it is not incorporated at present in a standard system. Thus, it is necessary to install a system which is designed with a special specification so as to be expensive and require a long delivery time. Further, the loop conveying device requires a large floor area so as to be contrary to the intension of cost reduction in the investment of plant and place including building. Further, since only a serial process is implemented, should one of units on a line fail, the entire line would come to a stop.
The present invention is made to solve the above-mentioned problems, and accordingly, an object of the present invention is to provide a manufacturing system and a manufacturing method which can shorten the time required for completing a series of process carried out for an object to be processed, and which is flexible and inexpensive so as to be able to produce any of even various kind of articles in a short time, suitable for a system for and a method of manufacturing a semiconductor so as to mainly carry out a piece process and a piece conveyance.
The above object can be achieved according to the present invention, in the following processes. With respect to a concept of a processing apparatus for transferring an object to be processed between a mini-environment type object (wafer or the like) storage container such as the one corresponding to a FOUP (Front Opening Unified Pod) or SMIF and the body of a processing unit which have been standardized for 300 mm diameter semiconductor processing units, by way of a robot located in an atmospheric pressure clean space (refer to SEMI-E106-0301 of SEMI Standards), there is provided such a configuration that a cleaned atmospheric conveying zone provided in a shield space, for each of a plurality of processing units within this concept is developed into a common atmospheric pressure conveying zone which is common among the processing units so as to constitute each of a plurality of process modules, and sample transferring places are laid among the plurality of process modules, and between the process modules and the conveying and transferring zone in order to process a sample by way of the plurality of modules.
According to the above-mentioned configuration for solving the problems, since the concept for piece process sequence is applied for each of the plurality of process modules (which will be hereinafter abbreviated as xe2x80x9csubsystemxe2x80x9d), the process waiting time required for each adjacent processing units and caused during a lot process can be greatly reduced, and the total time from the introduction of a sample to the completion for the sample can be greatly shortened. Further, since each of the processing units is built up with the processing units by a relatively small number, the load of the common atmospheric pressure conveying device part is greatly reduced, whereby it is possible to prevent the through-put of the process modules from being lowered even on a mass-production base.
If a series of units for a multi-layer wiring process which carries out repetition of treatment or the like, is composed of these subsystems with the above-mentioned concept, the above-mentioned technical effects and advantages can become higher.
Since the conveyance between the above-mentioned subsystems or between the subsystem and a conventional device can be used in combination with conventional lot conveyance (AGV, RGV, OHS, OHT or the like) with the use of a mini-environment type object storage container such a FOUP, the degree of freedom of the system can be greatly enhanced in comparison with the conventional configuration in which the conveyance is limited only to the piece conveyance.
Specifically, the present invention provides a system and a method as explained below:
According to the present invention, there is provided a wafer manufacturing system incorporating a plurality of processing units each having therein a conveyance mechanism and laid in a line, and an inter-unit conveyer devices for conveying an object to be processed between the processing devices, the inter-unit conveyer device having a loader conveying means laid along object transferring ports of the plurality of processing units which are arranged in a line, and extending across more than two of the object transferring ports, the loader conveying means being arranged herein with a running robot which runs among more than two of the object transferring ports and a transferring robot for transferring the object to be processed on the running robot onto one of the processing units, and further, the inter-unit conveyer device being shielded and provided with a purifying device so as to define an atmospheric pressure space conveying path, and being arranged in the atmosphere.
According to the present invention, there is provided a a wafer manufacturing method comprising the steps of processing objects to be processed by means of a plurality of processing units each having at least one processing chamber and a conveying mechanism, temporarily storing the objects to be processed in order to introduce or deliver the object to be processed, conveying an object to be processed to a position around a desired one of the plurality of processing units through an atmospheric pressure clean space path in a loader conveying means, transferring the object to be processed between the desired processing unit and each of the loader conveying means with a timing which is different among the processing units, transferring the object to and from the loader conveying means through the atmospheric pressure space path therein, and conveying the same.
Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings.